Is it E?

Nothing else makes more sense.

stop@800 wrote:Because Halley’s comet changes orbit slightly during the seventy-six-year interval between passing close to Earth, it may veer onto a collision course with a planet sometime in the distant future.

A between passing
B of passing
C between its passes
D of its passes
E as it passes

Please give proper reasoning also.

OA later...

Thanks

I reckon C. An 'interval' happens between 2 events/parts and the 'it' refers to the subject of the sentence 'Haley's comet'.

The OA is C

stop@800 wrote:Because Halley’s comet changes orbit slightly during the seventy-six-year interval between passing close to Earth, it may veer onto a collision course with a planet sometime in the distant future.

A between passing
B of passing
C between its passes
D of its passes
E as it passes

Please give proper reasoning also.

OA later...

Thanks

"between" needs to have 2 reference points.

"between passing" doesn't have any reference points at all, so is incorrect.

"between its passes" tells us that we're counting the time gap between each pair of passes, which is gramatically correct and makes sense (always a bonus!), so is the correct choice.

Neither "of" nor "as" correctly conveys the meaning of the sentence.