Twentieth-century sculpture was more abstract than realistic, especially when artists human form.
a. had depicted
b. are depicting
c. depicted
d. depict

A

Explanation:

Had depicted

Because it is far past so we will use past perfect tense

Twentieth-century sculpture was more abstract than realistic, especially when artists depicted human form.

Option - C

Explanation:

With the word "was" which is the "singular past of be-verb" we can identify that the first part of the sentence is given in the past tense.

So, here in the blank, we have to use the past tense form of the word "depict" that is depicted.

Past Tense: It is used to describe situations or things that have happened already

(Example: yesterday, earlier in the day, ten years ago, last week).

a) he encouraged islamic schools to introduce greek texts.

d) he invited greek scholars to teach their texts to the locals.

explanation: