Which of the following is not a granulocyte?

$A$ person with antigens '$B$' in $RBC$ and antibodies '$a$' (anti-$A$) in the plasma belongs to the blood group

Which of the following statements are correct regarding thrombocytes?
$I$ - Also known as blood platelets.
$II$ - They are cell fragments.
$III$ - Produced from megakaryocytes.
$IV$ - Their count in a normal individual ranges from $3,50,000$ to $6,00,000$ per $mm^3$.
$V$ - Involved in the process of blood coagulation.

Which of the following plasma proteins is responsible for maintaining the colloid osmotic pressure of the blood?

$A$ person with antigens $A$ and $B$ and no antibodies belongs to which blood group?

. . . . . . is a major storehouse of erythrocytes.