The antibodies produced in allergic reactions:

It is measured as part of a blood test and depends on the number and size of red blood cells. It is normally 40.7–50.3% for males and 36.1–44.3% for females.
Red blood cells contain hemoglobin, which transports oxygen and nutrients to the cells and tissues of the body.
Choice A is wrong because the color of plasma is not hematocrit.
Plasma is the liquid part of blood that carries blood cells and other substances.
Choice B is wrong because hematocrit is not a disease.
It is a test that can indicate conditions such as anemia or polycythemia.
Choice C is wrong because hematocrit is not a clotting factor.
Clotting factors are proteins that help the blood to clot and prevent bleeding.

The radial artery is one of the major blood-supplying vessels to the forearm and hand.
It can be felt as a pulse near the thumb on the wrist by gently pressing the artery against the underlying bone.
This is the most commonly measured pulse by nurses to assess peripheral pulse characteristics.
Choice B.
Palmar arch arteries are wrong because these are branches of the radial and ulnar arteries that form anastomosis in the palm of the hand.
They are not palpable on the wrist.
Choice C.
The brachial artery is wrong because this is the main artery of the upper arm that bifurcates into the radial and ulnar arteries at the cubital fossa.
It can be felt as a pulse in the antecubital fossa, not near the thumb on the wrist.
Choice D
The Ulnar artery is wrong because this is another major blood-supplying vessel to the forearm and hand that runs along the medial aspect of the forearm.
It can be felt as a pulse on the little finger side of the wrist, not near the thumb.