Which of the following describes the slowest change on earth's surface?

A) Gravity pulls an area of wet soil and rock downward in a landslide
B) An earthquake releases energy that built up below Earth's surface
C) Lava explodes from a volcano on an island
D) A canyon forms as water carries away weathered bits of rock

Which process takes the longest time?

A) The wind erodes a sand dune on the beach
B) A maple tree grows to be 100 feet tall
C) High mountains are eroded to gentle hills
D) A river floods and changes its course

To determine the slowest change on the Earth's surface among the options given, we need to understand the processes involved in each option.

A) Gravity pulls an area of wet soil and rock downward in a landslide: Landslides involve the movement of soil and rock due to the force of gravity. This process can occur relatively quickly, especially in steep areas or areas with loose soil, and therefore is not the slowest change.

B) An earthquake releases energy that built up below Earth's surface: Earthquakes occur when tectonic plates beneath the Earth's surface shift or release built-up energy. The release of energy during an earthquake can cause rapid movement and shaking of the Earth's surface. Therefore, it is not the slowest change.

C) Lava explodes from a volcano on an island: Volcanic eruptions involve the eruption of molten rock (lava) and other materials from a volcano. While volcanic eruptions can vary in intensity and speed, they generally happen relatively quickly compared to other geological processes. Hence, it is not the slowest change.

D) A canyon forms as water carries away weathered bits of rock: Canyons form through the process of erosion, where water erodes and carries away weathered rock over an extended period. This gradual process of water wearing away rock and carving out a canyon is generally considered to be the slowest change among the given options.

Therefore, the correct answer is D) A canyon forms as water carries away weathered bits of rock.