Final answer:
The speech irregularities that should not cause concern for young preschoolers are articulation errors, additions in words, and distortions of sounds, which are all part of normal speech development.
Step-by-step explanation:
Speech irregularities for young preschoolers that should not cause concern include articulation errors, additions in words, and distortions of sounds. These are typical aspects of speech development as children learn to master the phonetics and rules of language. Preschoolers are at a stage where their understanding of language rules may lead to overgeneralizations, such as adding 's' to the end of a word to indicate plurality, leading to phrases like 'two gooses' instead of 'two geese'. This process indicates that they are actively learning and applying rules, even though they may not have mastered all the exceptions yet. Articulation, in particular, tends to improve with age, and initial errors are part of normal development. As such, the correct answer to the student's question is 'articulation errors,' 'additions in words,' and 'distortions of sounds'.