The Barley Stamp

What aspect of the Holy Temple service does the Barley Stamp commemorate?

1. Barley was part of the daily Tamid offering.

2. The first barley of the year was harvested on the second day of Passover.

3. The Passover matzot were made from barley.

4. During breaks in the Temple service the Levites used to drink a beer made from barley.

What's the correct answer? For a clue, click here!