Sound Audition uses "open-ended" audio questions. The open ended audition mimmicks what audio engineers go through when identifying what they hear — and making decisions on potential corrective action. The only way to truly test someones ear is by an open ended blind audition.
Some audio questions/examples have are considered "acceptable" — and have nothing wrong with them. An audio engineer must also know when a mix is "in the box of acceptablity." This is why some exampes used are considered "acceptable" and have been deamed "acceptable" by professional engineers in the audio field.
Take your audition on a good sound system and in a quiet environment. A higher end speaker/monitoring system or using quality headphones or in-ear monitoring is highly encouraged. Use of laptop speakers and/or low quality consumer grade headphones is not recommended.