Decade counter range clarification A decade (mod-10) counter cycles through how many decimal counts before recycling? Choose the best completion to reflect its 0–9 sequence.

Introduction / Context:
The term “decade counter” means a modulo-10 counter. It is common in digital systems for generating decimal digits or timing sequences. This item asks how many decimal counts the device produces before rolling over.

Given Data / Assumptions:

• Modulus is the number of distinct states in the counting sequence.
• A typical decade counter cycles through 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 and then returns to 0.
• Some decades are BCD-encoded; others can be decoded one-of-ten, but both have modulus 10.

Concept / Approach:
The key idea is that a decade counter encompasses ten states. While the highest displayed value is 9, the total number of distinct counts is 10. Therefore, the correct completion emphasizes the modulus rather than the printed maximum value.

Step-by-Step Solution:

Verification / Alternative check:
Inspect a 74xx90/74xx160/74xx4017 datasheet; the decade sections clearly indicate ten counts per cycle.

Why Other Options Are Wrong:
“9” confuses the highest numeral with count total. “15” corresponds to a 4-bit binary full modulus. “0” is not a count quantity.

Common Pitfalls:
Equating the maximum displayed digit (9) with the modulus. Always count the number of states, not the largest state label.

Final Answer:
10