Giving Reasons with BECAUSE OF and BECAUSE

Choose because of or because to complete each sentence.

1		______________ space travel is dangerous and expensive, few people go on space missions.
			A)	Because
			B)	Because of
2		No one could survive on the moon ___________ it has no atmosphere.
			A)	because
			B)	because of
3		____________ the success of the Mir space station, the United States and Russia are now building an international space station.
			A)	Because
			B)	Because of
4		We now a lot more about space ___________ the Hubble telescope.
			A)	because
			B)	because of
5		The stars are always in the sky, but we can't see them _________ the sun shines so brightly.
			A)	because
			B)	because of
6		__________________ the space shuttle, many more people can now travel in space.
			A)	Because
			B)	Because of