Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.

What we know about certain diseases are still not sufficient to prevent them from spreading easily among the population

A. What we know about

B. are

C. from spreading

D. among

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.

What we know about certain diseases are still not sufficient to prevent them from spreading easily among the population.

A. What we know about

B. are

C. from spreading

D. among

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.

What we know about (A) certain diseases are (B) still not sufficient to prevent them from spreading (C) easily among (D) the population.

A. What we know 

B. are 

C. from spreading

D. among 

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.

What we know about (A) certain diseases are (B) still not sufficient to prevent them from spreading (C) easily among (D) the population.

A. what we know about

B. are

C. from spreading

D. among

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions

(A) What we know about certain diseases (B) are still not sufficient to prevent them (C) from spreading easily (D) among the population

A. What we know about

B. are

C. from

D. among

Mark  the  letter  A,  B,  C  or  D  in  your  answer  sheet  to  indicate  the  underlined  part  that  needs correction in each of the following questions.

What we know about certain diseases are still not sufficient to prevent them from spreading easily among the population.

A. What we know about

B. are

C. from spreading            

D. among

* Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction in each of the following questions.

 Endemic diseases are diseases that habitual infect only those persons living within certain geographical limits.

A. Endemic diseases

B. that

C. habitual infect

D. living within