Final answer:
The word 'substandard' from the excerpt indicates a critical tone towards the educational situation by suggesting it is below acceptable levels.
Step-by-step explanation:
The word from the excerpt Filed By Students On Behalf of Students that demonstrates a critical tone regarding the educational situation is C. substandard. This term specifically connotes a level of quality that is below what is considered acceptable or normal, directly critiquing the educational conditions being discussed. In contrast, words like 'performance', 'conditions', and 'facilities' can be neutral and do not inherently convey a critical tone without additional context.