Score Histogram Including Empty Buckets

For question 1, count responses in the buckets 0-3, 4-6, 7-8 and 9-10, showing buckets with zero responses. Order by bucket start.

Table schema

Buckets(label VARCHAR(10), lo INT, hi INT)
Responses(id INT PRIMARY KEY, respondent INT, question INT, score INT)

Sample data

Buckets
label | lo | hi
0-3 | 0 | 3
4-6 | 4 | 6
7-8 | 7 | 8
9-10 | 9 | 10

Responses
id | respondent | question | score
1 | 1 | 1 | 9
2 | 1 | 2 | 4
3 | 2 | 1 | 7
4 | 2 | 2 | 5
5 | 3 | 1 | 10
6 | 3 | 2 | 5
7 | 4 | 1 | 3