You will be presented with triplets of objects, which will be assigned to the keys Z, X, and R.
In each trial, please indicate which object you think is the odd one out by pressing the corresponding key.
In other words, please choose the object that is the least similar to the other two.

Z: washboard, X: lifesaver, and R: aloe. You press <<R>>.
Z: moss, X: eclair, and R: hearing aid. You press <<Z>>.
Z: orchid, X: spear, and R: nutcracker. You press <<Z>>.
Z: catfish, X: trigger, and R: petri dish. You press <<Z>>.
Z: beaker, X: orangutan, and R: hairpin. You press <<X>>.
Z: lectern, X: lizard, and R: lemon. You press <<R>>.
Z: prism, X: chain, and R: alligator. You press <<R>>.
Z: tooth, X: fire alarm, and R: coffin. You press <<Z>>.
Z: ballot box, X: ashtray, and R: egg roll. You press <<Z>>.
Z: taxi, X: bottle opener, and R: gauge. You press <<Z>>.
Z: spool, X: nightstand, and R: cellphone. You press <<Z>>.
Z: creme brulee, X: flour, and R: bat. You press <<R>>.
Z: shopping cart, X: vacuum, and R: mashed potato. You press <<R>>.
Z: wind chimes, X: rake, and R: fern. You press <<Z>>.
Z: charcoal, X: toad, and R: tab. You press <<X>>.
Z: wick, X: boxer shorts, and R: forklift. You press <<R>>.
Z: guardrail, X: hot-water bottle, and R: pecan. You press <<R>>.
Z: log, X: toilet paper, and R: scanner. You press <<Z>>.
Z: guinea pig, X: sword, and R: tongue. You press <<Z>>.
Z: aloe, X: washboard, and R: lifesaver. You press <<Z>>.