The following sentence is missing a necessary colon or contains an unnecessary one. Select the answer option that will make the sentence correct. If the original
sentence is correct as is, select No change.
When Harry S. Truman ran for president in 1948, several factors supposedly were
working against him, the media, Republican candidate Thomas E. Dewey's
popularity, and Truman's own down-to-earth style.

When Harry S. Truman ran for president in 1948, several factors supposedly were working against him: the media, Republican candidate Thomas E. Dewey's popularity, and Truman's own down-to-earth style.

Explanation:

Colons are used before a list of items, which in this case are the factors working against Harry S. Truman.

a) he encouraged islamic schools to introduce greek texts.

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

explanation: