he molecular clock theory uses genetic traits to estimate

he molecular clock theory uses genetic traits to estimate how long ago various groups of organisms diverged evolutionarily from one another. Which of the following statements explains why this is considered to be a theory? 
 Many scientific investigations have provided evidence to support this as the best explanation of the data. This is an opinion held by a group of scientists that cannot be proven or disproven. Because many scientists interpret the same data differently, it cannot be considered anything more than a theory. This is an educated guess made by a scientist who published his findings for others to read.