In the following passage about the purpose of education, choose the most appropriate word to complete the blank: the quality of our educational curriculum as well as that of our _____ and students is likely to remain inadequate.

Introduction / Context:
This question is another part of the same passage discussing education. The writer talks about the quality of the educational curriculum and then adds a reference to a group of people along with students. The blank asks for the most suitable noun to complete the phrase our _____ and students so that the whole expression makes sense in the context of education and quality. Recognising typical collocations in educational discourse again helps to find the correct answer.

Given Data / Assumptions:
- The relevant sentence is: the quality of our educational curriculum as well as that of our _____ and students is likely to remain inadequate. - Options are friends, ideals, parents and teachers. - The writer is evaluating the state of education and the people directly involved in it. - Curriculum is an institutional element, while students are learners.

Concept / Approach:
To complete the blank, we look at which group naturally pairs with students in discussions about education. The three main stakeholders are teachers, students and parents. In most policy and philosophy texts, the phrase teachers and students is very common. Friends and ideals do not fit because they do not refer to a clear stakeholder group whose quality is being assessed. Parents are important, but the phrase quality of our parents is unusual, whereas quality of our teachers is a standard expression. Thus teachers is the most likely answer.

Step-by-Step Solution:
Step 1: Recognise that curriculum, teachers and students form a meaningful trio representing the educational system: content, deliverers and receivers. Step 2: Insert teachers into the blank: the quality of our educational curriculum as well as that of our teachers and students is likely to remain inadequate. This is a natural and common phrasing in educational writing. Step 3: Test friends in the blank. The quality of our friends and students is logically odd and does not reflect standard educational vocabulary. Step 4: Test ideals. The quality of our ideals and students mixes an abstract concept with a group of people and sounds unbalanced. Step 5: Test parents. The quality of our parents and students is also an unusual phrase. Writers would more likely talk about support of parents, not quality of parents.

Verification / Alternative check:
We can confirm by comparing with common phrases used in education policy documents and reports, which frequently mention teacher quality and student quality. For example, one often reads about raising the quality of teachers and improving student learning outcomes. This pattern strongly supports teachers as the missing word. Also, when the curriculum is mentioned along with people, the natural triad is curriculum, teachers and students, not curriculum, parents and students or curriculum, friends and students.

Why Other Options Are Wrong:
Option A: Friends are not a formal part of the education system in this context. Referring to the quality of our friends does not match the serious tone of the passage. Option B: Ideals are abstract principles. The quality of our ideals is a possible phrase, but combining it with students as if both are being graded together is stylistically awkward. Option C: Parents are stakeholders in education, but writers do not usually talk about the quality of parents. Instead they speak of parental support or involvement, so this option is less natural.

Common Pitfalls:
A typical mistake is to select parents because they are strongly associated with children and education in everyday life. However, exam passages often reflect the formal language of policymakers and educational thinkers, who usually focus on teachers and students as the central human elements. Always check that the noun fits both grammatically and stylistically with the rest of the sentence and the broader context.

Final Answer:
The word that best completes the phrase is teachers, so option D is correct.