Question 942091
To find "A \ C" you start with set A and kick out numbers that are in set C. 


So we start with A = { 1, 4, 7, 10 } and kick out 4 since 4 is in C 


So


A \ C = { 1, 7, 10 }



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B ∩ (A \ C) turns into { 1, 2, 3, 4, 5 } ∩ { 1, 7, 10 }


Only the number "1" is in both sets, so { 1, 2, 3, 4, 5 } ∩ { 1, 7, 10 } = { 1 }


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Answer: 


B &#8745; (A \ C)  = <font color="red">{ 1 }</font>


There seems to be a typo somewhere in your answer choices or in the original question.