Explanation:
Bronsted acids are the species which donate protons.
In the given species, we can see that fluorine is the most electronegative atom hence, [tex]H_{2}F^{+}[/tex] will not give proton easily. Therefore, its acidity will be the least.
Similarly, sulfur is also electronegative but less electronegative than fluorine atom. Hence, acidity of [tex]CH_{3}SH_{2}^{+}[/tex] is slightly more than [tex]H_{2}F^{+}[/tex].
Whereas [tex]CH_{3}OH[/tex] will have highest bronsted acidity and [tex](CH_{3})_{2}OH^{+}[/tex] will be less acidic than [tex]CH_{3}OH[/tex].
Thus, we can conclude that order of increasing bronsted acidity is as follows.
[tex]H_{2}F^{+}[/tex] < [tex]CH_{3}SH_{2}^{+}[/tex] < [tex](CH_{3})_{2}OH^{+}[/tex] < [tex]CH_{3}OH[/tex]