Which type of muscles have a predictable tendency towards tightness?

The correct answer is postural muscles.

Postural muscles are muscles with the function to sustain posture in the gravity field. In response to stimuli such as over-use, under-use or trauma, postural muscles tend to shorten. This type of muscles is sometimes called  tonic muscles because they have high resting tonus.

the answer to your question is sperm

the main thing i would use is bricks because if there is a hurricane, there is a great possibility for the house to still stand. and i would also use plexiglass windows instead of regular windows because plexiglass isn't prone to breaking.