The ability to analyze and diagnose a situation and to distinguish between cause and effect demonstrates a manager's skills.

Conceptual

Explanation:

The conceptual skills are the abilities of the individuals to understand and interpret the situations and find or provide the solution to those problems. The conceptual skills developed by handling daily situations, thorough observation of the physical environment and these are also the products of cognitive abilities of the person.

The conceptual skills also emphasizes over the cause and effect relationship depending upon the problem, its associated effect on the individuals and related solution to the problem.

i would say b. research typically uses a variety of sources