Biology CLEP Prep Practice Exam

Vascular bundles in plants are composed of xylem and phloem tissues, which work together to transport water, nutrients, and sugars throughout the plant. Option A is incorrect because it does not include both xylem and phloem, which are both essential components of vascular bundles. Option C is incorrect because phloem and stem do not work together to transport substances, unlike xylem and phloem. Option D is also incorrect because roots do not contain xylem and phloem tissues, and therefore cannot be part of the vascular bundles.