In MS-DOS, which command-line utility quickly displays how much conventional/extended memory is available and in use?

Introduction / Context:
Diagnosing memory usage in DOS often requires a snapshot of conventional, upper, extended (XMS), and expanded (EMS) memory. Microsoft provided a small utility to summarize this information and list memory-resident drivers and programs.

Given Data / Assumptions:

• The question asks for the quickest command to view available memory.
• We are in a DOS/command-line setting.
• Utilities like CHKDSK focus on disks; MEMMAKER tunes memory but does not simply report it.

Concept / Approach:

The MEM command reports memory usage, including free and used amounts and details on drivers and TSRs when invoked with switches (e.g., MEM /C). It is the standard tool for a quick memory availability check in DOS.

Step-by-Step Solution:

Verification / Alternative check:

DOS help (MEM /?) confirms it displays the amount of used and free memory.

Why Other Options Are Wrong:

• EMM: not a DOS command; often refers to expanded memory managers (e.g., EMM386), not a reporting tool.
• CHKDSK: checks disks, not memory usage.
• MEMMAKER: attempts to optimize memory layout, not merely display it.

Common Pitfalls:

• Using MEMMAKER in place of MEM when only a quick report is needed.

Final Answer:

MEM.