Powerpoint Slide Question with Trigger answers

I am trying to setup a 'Question & Answers' 2007 ppt slide as follows:

- The top text box 1 asks the question; which appears as the slide opens.

- Below this are three separate text box answers vertically (numbered 2, 3, 4); which are required to be hidden as the slide opens.

- When any correct answer is provided (which can be in random order i.e. 2, 3 or 4), I click the associated keyboard text box numeral, which triggers that text box to unfold on the slide.  This similar procedure happens for each subsequent correct answer to the opening question, until all 3 answers are displayed.

- Please can you provide me with all the Animation steps to achieve this?  (I have tried, but have yet to succeed!)