In what has been called an earth-shattering discovery, evidence ...

[jlmhmf]

In what has been called an earth-shattering discovery, evidence of life on Mars was
  recently uncovered.
 
  A) adjective B) adverb C) noun

Question 2

Hydrocarbons are often found in sediment around decaying organisms, and iron
  sulfides and magnetite are compounds produced by microorganisms.
 
  A) independent clause B) dependent clause C) relative clause

[cupcake16]

Answer to Question 1

B

Answer to Question 2

A

[jlmhmf]

Thanks for the timely response, appreciate it

[bigsis44]

Excellent