The correct answer is:
All of the above
From ITF Rule 26:
Although it’s rare, in this case, all of the choices are valid depending on the rationale given. According to ITF Rule 26, Isabella’s team could have asked to replay the point because her partner was hindered by “something outside the player’s own control,” but their opponents could have also asked to replay the point because the coughing hindered them. In the second case, the opponents could not have claimed the point outright because it was an unintentional hindrance. The players were also right to continue play, thus making all of the answers valid.
