To solve this problem, we need to analyze each option and determine which pair is correctly matched. Let's evaluate each option:$\newline \bullet$Option 1: Large colorless empty cells in the epidermis of grass leaves - Subsidiary cells$\newline$ - In grass leaves, the large colorless empty cells are known as bulliform cells, not subsidiary cells.$\newline$ - Subsidiary cells are associated with guard cells in the stomatal complex.$\newline$ - Therefore, this option is incorrect.$\newline \bullet$Option 2: In dicot leaves, vascular bundles are surrounded by large thick-walled cells - Conjunctive tissue$\newline$ - In dicot leaves, the vascular bundles are surrounded by a bundle sheath, not conjunctive tissue.$\newline$ - Conjunctive tissue is found in the root and stem, not specifically surrounding vascular bundles in leaves.$\newline$ - Therefore, this option is incorrect.$\newline \bullet$Option 3: Cells of medullary rays that form part of the cambial ring - Interfascicular cambium$\newline$ - In dicot stems, the cells of medullary rays between vascular bundles can become meristematic and form the interfascicular cambium.$\newline$ - This interfascicular cambium, along with the fascicular cambium, forms the complete cambial ring.$\newline$ - Therefore, this option is correct.$\newline \bullet$Option 4: Loose parenchyma cells rupturing the epidermis and forming a lens-shaped opening in bark - Spongy parenchyma$\newline$ - The loose parenchyma cells that rupture the epidermis and form lens-shaped openings in bark are called lenticels, not spongy parenchyma.$\newline$ - Spongy parenchyma refers to the loosely arranged parenchyma cells in the mesophyll of leaves.$\newline$ - Therefore, this option is incorrect.$\newline$Based on the analysis, the correct pair is:$\newline$Option 3: Cells of medullary rays that form part of the cambial ring - Interfascicular cambium$\newline$Thus, the correct option is Option 3.