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One of the most important questions they had to consider was_____of public health

A. what             B. this           C. that            D. which

One of the most important questions they had to consider was__________ of public health

A. what         B. this

C. that         D. which

One of the most important questions they had to consider was  of public health

A. what              B. this              C. that               D. which

One of the most important questions they had to consider was _____ of public health.

A. what                      B. this

C. that                       D. which

 One of the most important questions they had to consider was      of public health

A. what      B. this               C. that         D. which              

One of the most important questions they had to consider was _____ of public health.

A. what                      B. this

C. that                       D. which

One of the most important questions they had to consider was         of public health.

One of the most important questions they had to consider was ______ of public health.

One of the most important questions they had to consider was ______ of public health.

A．what             B．this              C．which            D．that

One of the most important questions they had to consider was         of public health.