Please give me correct or fast answer and in hindi

by picture​

Ben is interested in using a source that provides original research, current and developing trends and experts within specific fields. which source should he use?

Layer r contains a well-known index fossil that is 100 million years old. based on this information and the principle of superposition, a. layers t and m are older than 100 million years, and layers x and g are younger than 100 million years. b. layers t, m, x, and g are all older than 100 million years. c. layers t and m are younger than 100 million years, and layers x and g are older than 100 million years.

At work claire has a deadline that is rapidly approaching as she works she finds that she is doing more work in a shorter amount of time than usual she thinks more quickly and her senses and memory are sharper what is responsible for claire working more efficiently