The correct answer is C) They can transport passengers to remote locations that do not have airstrips.
Step-by-step explanation:
Seaplanes are special planes designed to take off and land over water. This implies, different from regular planes seaplanes do not require airstrips or similar infrastructures but just a big body of water. Due to this, some airlines include seaplanes, considering with this they can transport passengers to locations where there are no airports or airstrips (Option D), for example, small islands in the middle of the ocean. This contributes to airline companies because it expands the type of flies they can cover or the services they offer.