2015-June-Q1a-(ii) analyse competition within the mobile operator industry

Compared to 2013-June-Q2a, which also covers five forces theory.
I wonder where they come from, cuz I cannot get these from the question.

“The products purchased from suppliers represent a significant fraction of the buyer’s cost. Buying is price sensitive and the company is likely to spend a great deal of effort trying to ensure the best terms of supply.
Purchasing companies are fewer and larger than potential suppliers. Suppliers may have alternative customers but their scope is limited. In contrast, the buying companies have many smaller supplying companies competing for their business.”

Thanks in advance.