The correct answer is D. Sentence 1 (Making rice pudding can be very easy)
Step-by-step explanation:
A topic sentence is a sentence in a paragraph that summarizes the idea of a paragraph or explains briefly what the paragraph is about. Topic sentences are usually the first sentences in the paragraphs of a text and help the reader know the main idea of each paragraph; also, these ideas support the general idea of the text. In this case, the paragraph includes a set of instructions on how to prepare a pudding rice, which means the main idea of this paragraph can be summarized in sentence 1 "Making rice pudding can be very easy", as this idea tells the reader introduces the topic on the reader and by telling the process is very easy the reader knows the paragraph will explain the steps of the process.