50. To make each paragraph clear, we must include a topic sentence. _________
(1) The readers will be lost because the topic is not clearly stated.
(2) Without the topic sentence, a paragraph is out of control.
(3) Most often the topic sentence comes first, at the beginning of a paragraph.
(4) And then the main point made in the topic sentence is developed and supported by the rest of a paragraph.
(A) 4123
(B) 2341
(C) 1234
(D) 2134