Two structure questions, please indicate correct answers and why, please!

1. The ability to communicate ideas and instructions was ___ for the incredible development of the frontal brain lobe in human beings.
A. necessary all that
B. all that was necessary
C. all the necessities that
D. such that all the necessities

2. Sunlight during dawn or dusk comes in at a lower angle, and since it cannot escape the dust and pollution of the atmosphere___, the sky turns orange and then red.
A. as can the daytime sunlight
B. can the daytime sunlight
C. so can daytime sunlight
D. as with daytime sunlight can