If the emission lines in the spectrum of one object are more strongly blueshifted than those from a second object, then the first object is moving
a. toward us faster than the second object.
b. away from us slower than the second object.
c. away from us faster than the second object.
td. oward us slower than the second object.

a). Toward us faster than the second object.

Explanation:

According to the wave nature of light if the object is moving than its spectral lines will be shift.This shifting of spectral lines is known as Doppler effect.

if the two objects are moving towards each other it means that wave is compressed and the wavelength is shorter.Then the lines will be shift toward shorter wavelength if known as blue shift.

So the option a is correct.

a. toward us faster than the second object.

compass can be used day and night, cloudy or sunny