Answer:
A and B are equally likely
Explanation:
The conditional probability is defined as follows:

where:
is the probability for X to occur, given that Y has occurred
is the probability that both X and Y occur at the same time
is the probability for Y to occur
Given two events A and B, we have:

and

In this problem, we are told that

Which means that:

Simplifying, we get:

which means that A and B are equally likely.
Answer:
on land but close to oceans
Explanation:
A boundary between an oceanic plate and a continental plate will be near a coastline., not "far from the coast" or "in the middle of oceans."
Often, mountains are also near that boundary, but mountains may also exist elsewhere, so "anywhere there are mountains" is not an apt description.
The best choice is "on land but close to oceans."
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<em>Additional comment</em>
The 2011 Tohoku earthquake near Japan was offshore by 67 km. It came from the subduction zone where the Pacific plate dives beneath the Eurasian plate. It is an example of a plate boundary quake that occurred offshore, rather than on land.
Answer:
Oceanic Lithosphere
Explanatation
Oceanic lithosphere is more dense (compacted by immense pressure from oceans) and the continental lithosphere is less dense (lack of pressure from anything above it). When the two collide, the continental lithosphere will essentially float on top of subterranean magma while the oceanic lithosphere, being the denser of the two, will slip beneath the continental lithosphere and dive into the magma chamber.
D the Stratosphere
hope that helps