The correct option is A Indian temples are a storehouse of Indian art.
Indian temples are the main focus in the sentence, they are being talked about, as indicated by the verb are. Thus, Indian temples is the subject of the sentence. The rest of the sentence is what is being talked about the subject, i.e., it is the predicate. In Option A, the subject and the predicate are arranged in a manner that makes complete sense and, thus, is correct which the statements of the other options fail to do.