Answer: C
Correct answer: Returns a specified value when a formula produces an error, and the result otherwise
IFERROR takes two arguments: a formula and a value to return if that formula produces any error. =IFERROR(A1/B1,0) gives the quotient normally and 0 when B1 is empty or zero. It is the concise replacement for the older =IF(ISERROR(x),y,x), which had to evaluate the formula twice. Its convenience is also its risk. It catches every error type, so a genuine #REF! from a deleted column is hidden just as quietly as an expected #DIV/0!. A formula wrapped in IFERROR can be silently wrong for months. Where only one error is expected, the more precise tools are better: IFNA catches only #N/A, which is the right choice around a lookup, and an explicit test such as =IF(B1=0,"",A1/B1) guards the actual condition. The second option describes ISERROR, which returns a logical value rather than substituting one.