The correct answer is option C, the age of rocks in various places in the ocean
Reason -
Glomar Challenger was a deep ocean study conducted by the American National Science Foundation and University of California (Institution of Oceanography) between 1968 to 1983, and during the initial stages of the study i.e in 1968, sample from drilling cones was taken at different places, and then the age of the sediments collected was determined using the paleontologic and isotopic dating studies which further led to the conclusive evidences of sea floor spreading and plate tectonic movement at later stage of study.