Parallesim and Verb Tense

[hariharakarthi]

Scientists have trained their telescopes on Arp 229, a pair of merging galaxies, and saw stars exploding in numbers far greater than expected.

A. and saw stars exploding in numbers far greater than expected

B.and saw stars exploding in numbers far greater than they were expecting

C. and saw stars exploding in far greater numbers than expected

D. and seen stars exploding in far greater numbers than being expected

E. and have seen stars exploding in far greater numbers than expected


OA is E. But, if the Ans choice D is

and seen stars exploding in far greater numbers than expected. Then, is it correct to choose this answer over E

Which one of the below is correct?
1:Scientists have trained ... and seen ...
2:Scientists have tranined ..... and have seen....
Please explain in detail

Regards,
hhk

[goelmohit2002]

Scientists have trained their telescopes on Arp 229, a pair of merging galaxies, and saw stars exploding in numbers far greater than expected.

A. and saw stars exploding in numbers far greater than expected

B.and saw stars exploding in numbers far greater than they were expecting

C. and saw stars exploding in far greater numbers than expected

D. and seen stars exploding in far greater numbers than being expected

E. and have seen stars exploding in far greater numbers than expected


OA is E. But, if the Ans choice D is

and seen stars exploding in far greater numbers than expected. Then, is it correct to choose this answer over E

Which one of the below is correct?
1:Scientists have trained ... and seen ...
2:Scientists have tranined ..... and have seen....
Please explain in detail

Regards,
hhk

IMO both should be correct.....

There is one similar example in OG-10....Q113......that tests the similar concept....where have <verb1>......and <verb2>

where <verb1> and <verb2> are replaceable....

[hariharakarthi]

Please provide an the OG 10 Example, I don't have OG10.
Regards,
hhk

[goelmohit2002]

Please provide an the OG 10 Example, I don't have OG10.
Regards,
hhk

https://gmatclub.com/forum/sc-monkeys-on ... 51789.html

[enniguy]

Scientists have trained their telescopes on Arp 229, a pair of merging galaxies, and saw stars exploding in numbers far ***ater than expected.

A. and saw stars exploding in numbers far ***ater than expected

B.and saw stars exploding in numbers far ***ater than they were expecting

C. and saw stars exploding in far ***ater numbers than expected

D. and seen stars exploding in far ***ater numbers than being expected

E. and have seen stars exploding in far ***ater numbers than expected


OA is E. But, if the Ans choice D is

and seen stars exploding in far ***ater numbers than expected. Then, is it correct to choose this answer over E

Which one of the below is correct?
1:Scientists have trained ... and seen ...
2:Scientists have tranined ..... and have seen....
Please explain in detail

Regards,
hhk

There is nothing much to explain.
IMO, both will be perfectly fine. Option E and "modified" Option D will both maintain parallelism. In fact, "being" has been introduced in option D just to make it wrong.

Answering your other question,
1:Scientists have trained ... and seen ...
Here "have" is implied. So this is right
2:Scientists have trained ..... and have seen....
Here have is explicitly mentioned. So this is also right.