When To Vertically or Horizontally Align Independent Checkboxes

Given a form and a series of sequential checkboxes whose values and context are independent of each other, how should they be aligned on the form; vertically or horizontally?

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My thinking is that it should be horizontal, since placing them vertically makes them seem too related to each other (reminiscent of a "select all that apply"). Horizontal seems to remove that connection, and also reduces the amount of white-space on the form (though this may not be applicable to every form).