A reader can best combine the information in the excerpts to understand that managing the moon landing while the lunar module had 30 seconds left of fuel required intense concentration.
understand that having only 30 seconds of fuel could easily have become a disaster while Armstrong was landing the lunar module.
understand that Armstrong radioed mission control when the lunar module landed on the moon at 4:18 p. m. EDT.
understand that it was impossible for the lunar module to land on the moon with only 30 seconds left of fuel.
HEL

A reader can best combine the information in the excerpts to understand that having only 30 seconds of fuel could easily have become a disaster while Armstrong was landing the lunar module.

Explanation:

In the given two excerpts, the main focus is on the importance of intense and careful concentration. If not, even a small mistake could lead to a major disaster.

The statement that "now would not be the time for the two Bobs to miscalculate, miscount or lose . . . concentration" is a big and important aspect of the mission to be a success. This was because the spacecraft had just "30 seconds of fuel", dangerously close to any disaster if there's any delay or mistake.

Thus, the combination of the two excerpts can be best made to understand that the 30 seconds of fuel could easily lead to a disaster while Armstrong was landing the lunar module.

B

Explanation:

nature versus humanity!