The following text is for questions 35 to 37.

(Source: Publisher's document)

    With the right supplies, you can make your own pickles at home.

A Clean Start

    All supplies that you use must be very clean when you make pickles at home. A dirty jar or spoon can spoil an entire batch of pickles.

The Cucumber is King

    The perfect pickle is crunchy. It starts with a firm, fresh cucumber. To make fresh pickles, fill jars with freshly picked cucumbers. Then, pour a heated mixture of salt, vinegar, and spices into the jars. Seal the jars with clean caps. Allow the pickles to cool, and put the jars in a refrigerator. Write the date on the jars.

Timing is Everything

    Leave your homemade pickles in a refrigerator. Pay attention to the date on the jars. If you haven't eaten the pickles after six months, throw them away.

Other Pickled Foods

    In addition to making pickles at home, you can try pickling other vegetables. Pickled carrots, cauliflower, and garlic cloves make tasty snacks and give salad some extra flavor.

(Adopted from: Evan Moor, Daily Reading Comprehension Grade 5, USA: Educational Publishers, 2010.)

From the fact that we have to throw the pickles away after six months because ____.