Statement: An instruction on the hall ticket reads "Every candidate has to be in the examination hall before the examination commences. Not even a late by 1 min is allowed."
I. If not mentioned in the hall ticket, candidates may come to the exam at any time as per their wish.
II. In a competitive examination, every candidate should be given an equal chance of writing the exam so as to filter the meritorious students.

I takes the rule and inverts it — claiming that without the instruction, anything goes. A rule being stated tells you nothing about what its absence would permit. Not implicit.
II is exactly what such a rule exists for: uniform conditions so that the test measures merit. Remove this belief and the strictness makes no sense. Implicit.
Answer: Only assumption II is implicit.

Statement: The national education policy brings major changes in the education system.
I. The present education system is not supporting the needs of the nation.
II. The present education system is teacher centric.

I underlies the statement — you do not make major changes to something working well. Implicit.
II names a specific defect the statement never mentions. The changes could concern funding, assessment, or structure. Too specific to be assumed. Not implicit.
Answer: Only assumption I is implicit.
Note the pattern: the general assumption survives, the specific one fails. This recurs constantly in assumption questions.

Statement: "Marriages are made in Heaven."
I. It is a divine power that ultimately decides who should marry whom.
II. Marriages are made in heaven before the couple even meet on earth.

I is essentially what the saying means — the pairing is decided by a higher power. Follows.
II adds a claim about timing ("before the couple even meet") that the statement never makes. Does not follow.
Answer: Only I follows.
Method: when an option adds a detail of time, quantity or degree that the statement omits, it almost always fails the conclusion test.

Statement: One of the Prime Ministers of India said, "Wastage of anything is crime. Wastage of food is double crime."
I. The issue of food wastage is of high importance to fight hunger, raise income and improve food security in India.
II. Food wastage is morally wrong because there are many people who are hungry simply because they have no food.

II tracks the statement closely — calling food wastage a "double crime" is a moral judgement, and hunger is the obvious reason food is singled out. It follows comfortably.
I is more contestable. "High importance" and "food security" are fair readings, but "raise income" is a policy consequence the statement never touches.
This question is worth studying precisely because it is arguable. Under exam convention the broad inference in I is usually accepted alongside II, but a strict reading rejects it on the income clause. If you meet an option like this, prefer the conclusion that stays closest to the words given.