You forgot to include the following choices but no worries I did this question before and the answers are:
advances in technology
increases understanding on environment
etc
Answer:
In animal field studies, why do scientists usually try to work without making the animals aware that the humans are present? It is necessary to observe the animals without disturbing them. When a controlled experiment is not possible, why do scientists try to identify as many relevant variables as possible?
Feel free to ask if you still don't understand
Because one has rule A so it wouldn't make Sense.
Answer:
<h2>
Cockroaches are generalized insects with few special adaptations, and may be among the most primitive living Neopteran insects. They have a relatively small head and a broad, flattened body, and most species are reddish-brown to dark brown. They have large compound eyes, two ocelli, and long, flexible antennae.</h2>
three pairs
Thorax. On the thorax, all cockroaches have three pairs of legs. Adults of most of the domestic species have two pairs of wings, although one species, the oriental cockroach, has poorly- developed wings in both sexes.
