DNA is the correct answer but next time put answer choices so that people can better answer your questions. Thanks!
C, the first two don't make sense and the last one would support the opposing view point.
It will get lower since the pressure around the barometer gets lower
If the star is receding, the pattern moves to longer, redder wavelengths. This is called redshift. Edwin Hubble used the Doppler effect<span> to determine that the universe is expanding. ... This red shift indicates that stars are moving away from us and from each other.</span>