Q: Tar sands are rocky materials mixed with what?


Read this paragraph and choose the correct option from the provided answers:

Tar sands are rocky materials mixed with very thick oil. The tar is too thick to pump, and so tar sands are strip-mined. Hot water and caustic soda are used to separate the oil from the rock. This creates a slurry, which is shaken. The oil floats to the top and is skimmed off.

 Choices:

- shale

- coal

- magma

- very thick oil


A:
very thick oil