The correct option is A Simple Sentence
A simple sentence is made up of only one clause, with one subject and
one verb. The given sentence contains one subject "I" and one verb "prefer", "taking a single good photo... ." is a gerund phrase that functions as the object. Hence it is a simple sentence and option A is correct. A complex sentence requires at least one dependent and one independent clause. Similarly, a compound sentence requires two independent clauses. Since the given sentence contains one clause, options B and C are incorrect. Option D is incorrect because the answer lies in A.
Note: 'Rather than' when followed by a gerund (verb + ing), functions as a preposition. When followed by an infinitive (to + verb) it functions as a conjunction.