All of the online classes I am taking include English, is excellent Correct
Change all to same
Change is to are
Change taking to took

Change is to are

Explanation:

The correct example sentence is:

All of the online classes I am taking, including English, is excellent .

In this sentence, the word is should be changed to are. This is the form of the verb to be in the present tense and it changes according to the rest of the sentence – which person it is and which number of subjects are in question.

The subject of the sentence is "online classes" (or just "classes"). This is the third person, which is how we know it is the third person.

However, the verb is should be used when the subject is singular.

Here the subject is plural (classes – we see the s at the end which marks the plural). Therefore the verb used should also be in the plural – which is are.

The correct form of the sentence at the end should be

All of the online classes I am taking, including English, are excellent.

the answer is   c the cold war