The adjective 'unreliable' is formed from the verb 'rely'. Which option correctly analyzes its formation?

1. Prefix 'un-' (negation) + verb base 'rely' + suffix '-able' (capability), forming an adjective meaning 'not able to be relied on'
2. Suffix '-un' (repetition) + noun 'reli' + prefix 'able'
3. A loanword imported directly from Latin without any internal structure
4. Two unrelated words joined by a hyphen in informal writing