This question is primarily testing MODIFIERS and LOGICAL PARALLELISM.

Researchers have found entombed in Burmese amber a 102-million-year-old tick grasping the feather of a Velociraptor, providing the first direct evidence that the tiny pests drank dinosaur blood.

(A) entombed in Burmese amber a 102-million-year-old tick grasping the feather of a Velociraptor, providing
The placement of the modifier "entombed" may sound strange to some ears, but there is nothing grammatically or logically incorrect with this construction.

(B) entombed in Burmese amber a 102-million-year-old tick grasping the feather of a Velociraptor and providing
- the list "grasping and providing" implies that these are both parallel actions that the tick is performing. The tick alone isn't directly providing evidence; the fact that this tick is grasping the feather is providing the evidence.

(C) a 102-million-year-old tick grasping the feather of a Velociraptor entombed in Burmese amber and providing
- ambiguous modifier: "the feather of a velociraptor entombed..." makes it sound like the velociraptor (or its feather, since modifiers can 'hop' over a preposition to modify a whole noun phrase) was entombed, and the tick is perhaps grasping the amber. Other answers make clearer that the tick + feather is the thing entombed in amber.
- same parallelism/meaning issue as in B.

(D) a 102-million-year-old tick grasping the feather of a Velociraptor entombed in Burmese amber, which provided
- same ambiguous modifier as in C.
- "which provided" makes it sound like the amber itself (or perhaps the feather or the velociraptor) is the thing providing evidence. We don't want to use a noun modifier here; it is the entire idea that this tick is grasping the feather than provides evidence, so we want to use an adverbial modifier such as "providing..." to modify that whole clause.

(E) a 102-million-year-old tick, entombed in Burmese amber, grasping the feather of a Velociraptor and providing
- same parallelism issue as in B.

The answer is A.