Why is history open to ongoing and changing interpretations?

a) changing values limit interpretation.
b) new evidence is not available.
c) primary sources are determined to be unreliable.
d) revisionists are overruled by traditionalists.
e) traditional interpretations are questioned by revisionists.

i think the answer is c, rivers.

explanation:

sometimes, borders fall along natural boundaries like rivers or mountain ranges. for example, the boundary between france and spain follows the crest of the pyrenees mountains. for part of its length, the boundary between the united states and mexico follows a river called the rio grande. the borders of four countries divide africa’s lake chad: niger, chad, cameroon, and nigeria.

in the 1950s, country music came into its own before rock-n-roll took off in the 60s while jazz and classical music continued to innovate