Step 1: Place Omega taxonomy in the bigger picture.
Early or alpha taxonomy classified plants mostly by what you could see with the naked eye or a simple lens, shape of leaves, flowers and so on. Omega taxonomy is the modern upgrade that pulls in evidence from every other branch of botany to build a more accurate, evolution based classification, so the Assertion is correct.
Step 2: Check whether the named disciplines actually feed into Omega taxonomy.
Palynology examines pollen structure, embryology traces how the embryo develops, and phytochemistry looks at the chemical compounds a plant produces, and all three genuinely supply extra clues that refine and support advanced classification schemes.
Step 3: Connect the Reason back to the Assertion.
Because these disciplines are precisely the outside sources of information that Omega taxonomy draws on, the Reason directly explains why such classification is called Omega taxonomy in the first place.
Final answer: Option 1, both statements are correct and the Reason is the correct explanation of the Assertion.