Institution: Directorate of Primary Education - DPE Exam: Primary Exam Question Solution 24-05-2019
Topic: Idioms & Phrases, Subject: English Grammar (ইংরেজি গ্রামার)

Best Answer Explained in Below-:

Deciduous trees are defined by their unique characteristic of shedding their leaves annually, typically in the fall. This adaptation is critical for their survival in temperate climates, where seasonal changes can lead to harsh winter conditions. By losing their leaves, these trees reduce water loss and conserve energy during periods when photosynthesis—the process by which trees convert sunlight into energy—is less efficient due to reduced sunlight or freezing temperatures.

In contrast, evergreen trees retain their foliage throughout the year, allowing them to photosynthesize continuously, even in winter. The process of leaf loss in deciduous trees often coincides with changes in daylight and temperatures, signaling the trees to prepare for dormancy. When spring arrives, new leaves emerge, allowing these trees to maximize energy intake during the growing season.

The other options listed, such as having fleshy leaves or being extremely big, do not accurately describe the fundamental classification of deciduous trees, making D the correct answer. Understanding this cyclical pattern of leaf shedding is essential to recognize the adaptive strategies that help deciduous trees thrive in varying environmental conditions.