Over the last few decades, scientists have noticed that lobsters, which obtain heat from the environment rather than generating it themselves, are moving north at a rate of six kilometers per year.

what is the best explanation based on these observations?

Lobsters are adapting to cooler temperatures.

Explanation:

Adaptation may be defined as the phenomena that involves the physical, physiological and chemical changes in the organisms that helps to adapt themselves in their environmental condition.

The adaptation may bring genetic changes in the next generation as well. The lobsters movement per year demonstrates that they are trying to adapt in their environment. The cooler temperatures is favorable for the growth and adaptation of Lobsters.

Thus, the answer is Lobsters are adapting to cooler temperatures.

b. lithosphere, asthenosphere, mesosphere   is the answer most likely

when the displaced particles are perpendicular to the direction the wave travels, is called a transverse wave, whereas in longitudinal wave the displace practices are parallel to the direction of the wave.

in the given image:

first image shows - longitudinal wave

second image shows - transverse wave

third image shows - longitudinal wave

fourth image shows - longitudinal wave