How many credited seasons does Player M earn for the 2020 season?

To determine how many credited seasons Player M earns for the 2020 season, it's necessary to understand the criteria for earning a credited season in the NFL. A player typically earns one credited season if they are on a team's roster for at least three games during a regular season. Factors such as performance, being on injured reserve, or practice squads can influence credited seasons, but fundamentally, being active for a minimum period is key.

If Player M did not meet the minimum requirement due to not participating in a sufficient number of games or being inactive throughout the 2020 season, he would not earn any credited seasons for that year. This aligns with the assertion that Player M earns 0 credited seasons.

In contrast, the other options detail scenarios where the player would have been active enough to earn at least one credited season, which cannot hold true based on the given situation. Thus, the reasoning for declaring 0 credited seasons is grounded in the understanding of NFL eligibility criteria for credited seasons.