Planck’s quantum theory explains the emission and absorption of radiation. Postulates of Planck’s quantum theory are as follows:

(a) Different matter radiates energy or absorbs energy in discrete quantities discontinuously in the form of small bundles. These smallest bundles of energy can be emitted or absorbed in the form of electromagnetic radiation is known as quantum and in the presence of light, a quantum of light is known as a photon.

(b) The energy of the radiation absorbed or emitted is directly proportional to the frequency of the radiation.

(c) Energy less than quantum cannot be emitted or absorbed. A matter can radiate energy or absorb energy in the whole numbers which is a multiple of a quantum as nhv. Where n is a positive integer. So, the energy can be absorbed or radiate as hv, 2hv, 3hv, and so on; it can not be denoted as 1.5 hv, 2.5 hv, etc.

Hence, the correct option is (D).

Due to input and output symmetry P and Q and S and T have the same potential.

Feldspar, any of a group of aluminosilicate minerals that contain calcium, sodium, or potassium. Feldspars make up more than half of Earth's crust, and professional literature about them constitutes a large percentage of the literature of mineralogy.

The mineralogical composition of most feldspars can be expressed in terms of the ternary system Orthoclase (KAlSi₃O₈), Albite (NaAlSi₃O₈), and Anorthite (CaAl₂Si₂O₈). Chemically, the feldspars are silicates of aluminum, containing sodium, potassium, iron, calcium, or barium or combinations of these elements.

Zeolites transform to other minerals under weathering, hydrothermal alteration, or metamorphic conditions. 

Zeolites are crystalline solids structures made of silicon, aluminum, and oxygen that form a framework with cavities and channels inside where cations, water, and/or small molecules may reside. They are often also referred to as molecular sieves.
Hence, the correct option is (A).

Roots that arise from parts of the plant other than radicle are called adventitious roots. For example: In banyan, prop roots are found that grow vertically downward into the soil and spreading branches. Adventitious roots of sweet potato, get swollen and store food. The stems of maize and sugarcane have supporting roots coming out of the lower nodes of the stem. These are called stilt roots.

Hence, the correct option is (D).

The pericardial cavity is the potential space formed between the two layers of serous pericardium around the heart. Normally, it contains a small amount of serous fluid that acts to reduce surface tension and lubricate. Therefore, the cavity facilitates the free movement of the heart.

Hence, the correct option is (D).

In surface chemistry,

a. Dissipation/ Desorption is the process of removing an adsorbed substance from a surface on which it is absorbed.

 b. Absorption is a process in which the substance (adsorbate) is uniformly distributed throughout the bulk.

c. Sorption is a process where both the phenomenon of adsorption and absorption take place simultaneously.

d. Physisorption is a type of adsorption where weak Van der Waals forces a ct between the adsorbate and adsorbent.

Thus the correct combination of an answer will be a-(ii), b-(iii), c-(iv), d-(i).

Hence, the correct option is (B).