Multi-choice problem: Continue writing the next sentence in this paragraph:

How to make a gardening calendar
The usda plant hardiness zones help gardeners determine which plants are suitable for their local climates.
The plant hardiness zones are based on the average minimum winter temperatures. The gardening tasks required each month will vary depending on your usda plant hardiness zone.

Choices: a. To determine your zone, visit the usda website for an interactive map. Select a traditional wall calendar to use as a gardening calendar.; b. Temperatures in the usda plant hardiness zones are found in the western hemisphere. You can see the differing temperatures by hovering your mouse over plants at either end of the plant hardiness zones.; c. Usda hardiness zones usually involve removing crops from the ground for watering, pruning, planting, or even harvest periods. There is also some danger--the plants will experience ground rot.; d. The usda has a plant hardiness zone atlas online and at its website. You can then determine what plants will thrive best in your area and plans to move to a different one every two months.;
a.