The following are context clues phrases in the passage examples and syntax
There are many ways of seeing this, inlcluding that the whole sentence is the verbal phrase!
but minimally, it's
<span>Shouldn't have gone </span>- these definitely have to be in the verb phrase (C is the correct option)
<span>"So-called anonymous tracking is not very secure—the anonymity is fairly easily broken. Cracking [it]...is a fairly easy engineering feat."
This example maintains the main idea of the passage, keeping its message in tact while eliminating information using ellipses to improve clarity. The addition of "it" also helps make it clearer and more concise. </span>