The answer is D, Because dinosaurs appears in the Triassic period while insects appeared in the Devonian period which is about 160 million years about, which rules out A and B. Humans have been on Earth for almost 3 million years, which is nothing compared to the history of life in earth, which about 4,000 million years of life history, so D
A plant reaches its adult stage
when it is ready to reproduce.
The statement “All plants
reproduce several times before dying” is true. The answer is letter A. Plants
can reproduce several times as long as it has the gametes needed for
reproduction.
Beginning in the mid 1600's Earth entered into a mini-ice age. 1815 was known as the "year without a summer" and snow fell in many European countries during the summer months. The prolonged climate change is attributed to low sun spot activity, while the summer snow is believed to be the result of
A major volcanic eruption.
This is referred to as: spontaneous recovery
Spontaneous recovery is a theory of learning and memory which involves unexpected and recurrence of a conditioned response after a period of reduced response or delay. Spontaneous recovery is associated with classical conditioning and operant conditioning. Extinction will happen quickly after a spontaneous recovery, if the conditioned and unconditioned stimulus is not connected.