Difficulty: Easy
Correct Answer: The default value of numeric array elements is zero.
Explanation:
Introduction / Context:This conceptual MCQ checks basic facts about C# arrays: allowed element types, the meaning of rank and length, default initialization of elements, and whether arrays are automatically sorted by the runtime.
Given Data / Assumptions:
Concept / Approach:Arrays are reference types whose elements are initialized to default values (0 for numeric types, false for bool, null for reference types). Rank is the number of dimensions (e.g., 1 for int[], 2 for int[ , ]). Length is the total number of elements across all dimensions. No automatic sorting occurs upon creation or assignment.
Step-by-Step Solution:
Check each statement: A — False: arrays can hold any single element type, including reference types and user-defined structs. B — False: rank is dimension count, not total elements. C — False: length is total elements; rank is number of dimensions. D — True: numeric arrays default to 0 for all entries. E — False: elements are not automatically sorted.Verification / Alternative check:Create int[3] a = new int[3]; printing values shows 0 0 0; a.Rank returns 1; a.Length returns 3.
Why Other Options Are Wrong:They contradict the CLR definitions of rank, length, and default initialization, or claim an unsupported guarantee (sorting).
Common Pitfalls:Confusing rank with length, and assuming arrays of value types are uninitialized (they are zero-initialized by the runtime).
Final Answer:The default value of numeric array elements is zero.
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