Step 1: Analyzing Statement A
Saline hydrides such as sodium hydride (NaH) do release dihydrogen gas at the anode when electrolyzed. This statement is true.
Step 2: Analyzing Statement B
CH₄ (methane) is an electron-precise hydride because it follows the octet rule, and each carbon in CH₄ has exactly 4 bonds. This statement is true.
Step 3: Analyzing Statement C
Chromium hydride (CrH₆) is known to conduct both heat and electricity, like most metallic hydrides. This statement is true.
Step 4: Analyzing Statement D
Hydrides of group 15 elements, such as NH₃, do not behave as Lewis acids. They are more likely to act as Lewis bases due to the lone pair of electrons on nitrogen. Therefore, statement D is incorrect.