それが最善の方法だと思う。

that (indicating an item or person near the listener, the action of the listener, or something on their mind); it; that time; then; there (indicating a place near the listener); you

indicates sentence subject (occasionally object); indicates possessive (esp. in literary expressions); but; however; still; and

the very best

indicates possessive; nominalizes verbs and adjectives; substitutes for "ga" in subordinate phrases; (at sentence-end, falling tone) indicates a confident conclusion; (at sentence-end) indicates emotional emphasis; (at sentence-end, rising tone) indicates question

method; process; manner; way; means; technique

be; is; indicates past or completed action; indicates light imperative

if; when; and; with; particle used for quoting (with speech, thoughts, etc.); quoting particle; promoted pawn; indicates question (sentence end)

to think; to consider; to believe; to think (of doing); to plan (to do); to judge; to assess; to regard; to imagine; to suppose; to dream; to expect; to look forward to; to feel; to desire; to want; to recall; to remember