Question

reading about something to gain more knowledge is considered to be...
a descriptive investigation.
an experiment.
research.
a comparative investigation.

Explanation:

Research involves gathering information to gain knowledge. Reading about a topic to learn more fits this definition. A descriptive investigation focuses on describing phenomena, an experiment tests a hypothesis through manipulation, and a comparative investigation compares different things. Reading to learn is a form of research.

Answer:

C. research.