Identify the topic sentence:
Throughout the centuries, some form of written communication has been utilized. In earlier times, people carved or painted messages on rocks. People then began writing on pieces of leather, which were rolled into scrolls. With the dawn of the middle ages. The heavy paper called parchment was used for writing and books were laboriously hand-copied. With the advent of the printing press in the mid-fifteenth century, the modern printing industry came to life.

a) In earlier times people carved or painted messages on rocks.
b) Throughout the century, some form of written communication has been utilized.
c) With the advent of the printing press in the mid-fifteenth century, the modern printing industry came to life.
d) With the dawn of the Middle Ages, the heavy paper called parchment was used for writing, and books were laboriously hand copied.

Hint: A “topic sentence” is a sentence that is going to convey the meaning of the whole paragraph. It is exactly what it is: a topic. A topic of anything tells us what we can expect in the paragraph below it. Thus, we have to select the sentence from the options which best describes the given paragraph in one line.

Complete answer:
Option a talks about the fact that people used to carve or paint messages on rocks. It is a sentence that has been picked up straight from the paragraph. It talks about one part of the given paragraph only. This option is incorrect.

Option b gives us a summary of the paragraph- that it is talking about the utilization of some form of written communication by people and its evolution. So, the correct answer is “Option b”.

Option c is yet again a sentence picked out from the paragraph. It is talking about the mode of communication in the mid-fifteenth century and not giving an overall view of how communication methods have evolved.

Option d is talking about the mode of communication in the middle ages. It does not talk about the evolution of communication methods over the centuries. It is therefore the wrong answer.

Note:
The topic sentence should be such that it tells the readers about the whole paragraph and not pertain to any one fact or century. Options a, c, and d talk about specific ages in time and not about all the centuries. While selecting a topic sentence, make sure to select a sentence which tells you what you are about to read in the coming paragraph.