Which is a reason why congress uses its power to investigate?

Option C is correct. Check the complete question in the 'explanation' section.

Explanation:

Complete question: Which is a reason why congress uses its power to investigate? (a). To select the speaker of the house, (b). To ammend Constitution, (c). To oversee executive agency, (d). To ammend Constitution.

The power of the Congress to investigate is non-legislative. This power have been in effect since the 1700s. In the year 1792, United States of America House of Representatives investigated the defeat of General St. Clair and his army by the Indians in the Northwest.

The Investigations set by the Congress are used for testing effectiveness of laws, and to Gauge the performance of officials of the Congress and the officials of other arms of the government (the executive arm especially). Investigation are also conducted by the Congress to gather information about future legislations.

answer; validity;