Which of the following is the correct one?

1.   THE PIG THYMUS

A)      IS A SECONDARY ORGAN OF THE IMMUNE SYSTEM
B)      PRODUCES B LYMPHOCYTES
C)      INVOLUTES FROM THE FIRST YEAR OF LIFE
D)      NONE OF THE ABOVE IS CORRECT

2.   CAN YOU REMEMBER THE MAIN CHARACTERISTICS OF THE IMMUNE SYSTEM?

A)      SPECIFICITY
B)      MEMORY
C)      DISCERNS ITS OWN COMPONENTS FROM FOREIGN ONES
D)      RAPIDITY  

3.   PIG LYMPH NODES

A)      ARE THE SAME AS THOSE OF OTHER SPECIES
B)      ARE DIFFERENT IN THEIR STRUCTURE, BUT NOT IN THEIR CIRCULATION
C)      ARE DIFFERENT IN THEIR STRUCTURE AND THEIR CIRCULATION
D)      NONE OF THE ABOVE IS CORRECT 

4.    THE ORGANS OF THE SWINE IMMUNE SYSTEM CAN BE CLASSIFIED AS:

A)      PRIMARY AND SECONDARY
B)      SECONDARY AND LYMPHOID
C)      MIXED
D)      NONE OF THE ABOVE IS CORRECT

5.    THE B LYMPHOCYTES OF THE LYMPH NODES ARE USUALLY LOCATED IN:

A)      DIFFUSE LYMPHOID TISSUE
B)      LYMPHOID FOLLICLES
C)      BOTH
D)      NONE OF THE ABOVE IS CORRECT    

6.   A PIG'S SPLEEN:

A)      IS A PRIMARY LYMPHOID ORGAN
B)      IS A SECONDARY LYMPHOID ORGAN
C)      ONLY PRODUCES B LYMPHOCYTES
D)      ONLY PRODUCES ERYTHROCYTES