None of the above. Since English is largely an analytic language (with a few surviving synthetic characteristics), punctuation, grammar, and syntax are inextricably intertwined. Some elements of each survive independently of the others, but all three are involved in an interplay.
Consider the following:
“My parents made me a(n) ____.” The word that fills the blank clarifies (or, occasionally and humorously, fails to clarify) whether the meaning of the sentence is “My parents made [for] me a(n) ____” or “My parents made me [into] a(n) ___.” The “me” is in one case functioning as indirect object, beneficiary of an action, and in the other as direct object in a predicate copula – Subject acts in way specified by verb to transform direct object into ‘secondary object.’ (Grammarians will have a better term for the “product” noun in a predicate copula than the one I learned 40+ years ago, I’m sure.)
“Research indicates that gays who engaged in promiscuous sex were largely responsible for the early spread of AIDS” vs. “Research indicates that gays, who engaged in promiscuous sex, were largely responsible for the early spread of AIDS.” The first sentence suggests a debatable proposition in social epidemiology; the second implies an insulting indictment of all persons with same-sex orientation.
“Bulgaria’s avifauna includes many species of turkeys” vs. “Bulgaria’s avifauna includes many species of Turkey’s.” Galliform fowls or species from a neighboring country?
“Colibri’s expertise is more extensive than Miller’s.” (Comparison of two Dopers.) “Colibri’s expertise is more extensive than millers.” (Colibri has expertise in more fields than one family of lepidoptera.) “Colibri’s expertise is more extensive than Miller’s.” (Colibri has a wider expertise than some person named Miller, not the Doper.) “Colibri’s expertise is more extensive than millers’.” (Colibri has a more extensive expertise than people who grind grain for a living.)
And, of course, the old canard about the girl uttering a pro forma faux protest to her boyfriend: “Don’t! Stop! Don’t! Stop! Don’t stop! Don’t stop!” (Please don’t take this into a seduction/date-rape argument; it’s a relict of a time when a girl was supposed to make a protest to satisfy the proprieties, a social artifact of an older set of mores.)
“Randy loved one tin soldier.” (a boy’s attachment to a toy) “Randy loved ‘One Tin Soldier.’” (he was enamored of the Ronstadt song) “Randy loved One Tin Soldier.” (presumably a book this time)
One could also construct a sentence in which the singular, plural, singular possessive, and plural possessive were all properly used in an otherwise-identical structure, carrying distinctly different meanings.
All these examples are, of course, chosen for maximum value as examples, but illustrate how English grammar, syntax, and punctuation (and sometimes capitalization and typography) interact to modify meaning.