kaplan sc - About 7,500 years ago, a torrent of water

Is the OA A.

IMO both options D and E unnecessary use past perfect tense

when the meaning can be conveyed using past tense why use past perfect.

Both D and E sound extremely awkward.. not sure why they are wrong. A seems to be good. Is A the correct answer?

About 7,500 years ago, a torrent of water poured through the Bosporus into the Black Sea, raising the water level 500 feet within a year.

a. a torrent of water poured through the Bosporus into the Black Sea, raising the water level

Cause and effect. Water poured (cause) -> raising (effect). Hence we use gerund i.e. the ing form.

b. a torrent of water poured through the Bosporus into the Black Sea, which raised the water level
c. a torrent of water poured into the Black Sea through the Bosporus, which raised the water level
d. the Black Sea had a torrent of water poured into it through the Bosporus, raising the water level
e. the Black Sea had the water level raised by a torrent of water pouring into it through the Bosporus

Applies to both d and e.

Use passive voice. Also, two actions need to occur in the past for us to use had.

Action 1 (had) happens first
Action 2 (simple past) happens later

By the time we arrived at the movie hall, the movie had already started.

If there is a single action happening we use simple past.

hemant_rajput wrote:About 7,500 years ago, a torrent of water poured through the Bosporus into the Black Sea, raising the water level 500 feet within a year.
a. a torrent of water poured through the Bosporus into the Black Sea, raising the water level
b. a torrent of water poured through the Bosporus into the Black Sea, which raised the water level
c. a torrent of water poured into the Black Sea through the Bosporus, which raised the water level
d. the Black Sea had a torrent of water poured into it through the Bosporus, raising the water level
e. the Black Sea had the water level raised by a torrent of water pouring into it through the Bosporus

In B, which refers to the Black Sea, implying that the Black Sea raised the water level.
The intended meaning is that a TORRENT OF WATER raised the water level.
Eliminate B.

In C, which refers to the Bosphorus, implying that the Bosphorus raised the water level.
The intended meaning is that a TORRENT OF WATER raised the water level.
Eliminate C.

COMMA + VERBing serves to express an action brought about by the PRECEDING SUBJECT.
Thus, in D, raising refers to the Black Sea (the preceding subject), implying that the Black Sea was raising the water level.
The intended meaning is that a TORRENT OF WATER was raising the water level.
Eliminate D.

In E, pouring into it...500 feet does not convey the intended meaning.
The intended meaning is that the water level was RAISED 500 feet.
Eliminate E.

The correct answer is A.