What brine prepared spice is actually the unopened flower bud of a type of Mediterranean bush?

Capers are the unopened flower buds of the caper bush, which is native to the Mediterranean region. When harvested, these buds are typically preserved in brine or salt, which enhances their sour and salty flavor profile. This unique preparation is what makes capers distinct from the other options listed.

Cloves, on the other hand, are flower buds from a different species—clove trees found primarily in Indonesia. They are dried and used as a spice, but they do not come from a Mediterranean bush. Jalapeños are a type of chili pepper, while garlic is a bulbous plant that belongs to the onion family. Neither of these may be associated with brined flower buds. Therefore, capers stand out as the correct answer due to their specific characteristics and preparation method.