Confounding Variables in Insect Experiment: A,E,F

[Orion78]

An experiment is set up to test whether a particular insect prefer a dark or a bright environment. A chamber with a gradient in light intensity from one end (dark) to the other (bright) has been made. The experimental hypothesis is:
“There will be a large difference between the number of insect in a dark side and the number in a bright side of the chamber.”
Which one could be the three confounding variables?

A - Varying humidity across the chamber
B - The orientation of the chamber
C - The age of the insects
D - The non-reflective material from which the chamber is made
E - The type of light source used
F - Varying temperature across the chamber

I was thinking A, E and F but there is something wrong ..
Any help would be appreciated. Thanks

 

[Orion78]

Can anyone be able to help me with this question? Thanks

 

[epenguin]

An

An experiment is set up to test whether a particular insect prefer a dark or a bright environment. A chamber with a gradient in light intensity from one end (dark) to the other (bright) has been made. The experimental hypothesis is:
“There will be a large difference between the number of insect in a dark side and the number in a bright side of the chamber.”
Which one could be the three confounding variables?

A - Varying humidity across the chamber
B - The orientation of the chamber
C - The age of the insects
D - The non-reflective material from which the chamber is made
E - The type of light source used
F - Varying temperature across the chamber

I was thinking A, E and F but there is something wrong ..
Any help would be appreciated. Thanks

Well I suppose the question is intended to make you realize the difficulty and art of experimental design. But if it is presented as a box tick question, A,B or C without the opportunity of justifying reason, I would not worry too much about your answer not according with what Authority says.

It is true that false conclusions have sometimes been drawn because an effect was due to a less obvious variable.

Sometimes it will be hard to control for every imaginable variable factor and bets are made depending on plausibility.

For some of these factors an experiment to control for is easy.

Others, say the age of the insects, may possibly be a significant factor. Yet a positive result would be significant even in a mixed-age population. A negative result less so. If a mechanism kicks in or out at a certain age you may miss an effect if the insects are the wrong age. Sometimes things have been missed that way. You cannot do everything, can't always call not doing everything incompetence, so the intuition or insight or hunch of the researcher can count.

If the question requires you to condense the above paragraph to 'not C' it is rather a ridiculous question IMO.

Oh, and in real situations if you are allowed to ask 'Why do you want to know this?' then the answer may lead to more pertinent experimentation, but maybe that is a dangerous question in your artificial situation!

I guess you just try and eliminate from the list those factors that are uniform or that you think are uniform enough across the space of the chamber - considering that theory also tell you there is a LARGE preference by the insects.